LT1937: White LED Step-Up Converter in SC70 and ThinSOT Data Sheet8/28/2007362K
Features and Benefits
- Inherently Matched LED Current
- High Efficiency: 84% Typical
- Drives Up to Four LEDs from a 3.2V Supply
- Drives Up to Six LEDs from a 5V Supply
- 36V Rugged Bipolar Switch
- Fast 1.2MHz Switching Frequency
- Uses Tiny 1mm Tall Inductors
- Requires Only 0.22µF Output Capacitor
- Low Profile SC70 and ThinSOT™ Packaging
The LT1937 is a step-up DC/DC converter specifically designed to drive white LEDs with a constant current. The device can drive two, three or four LEDs in series from a Li-Ion cell. Series connection of the LEDs provides identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors. The LT1937 switches at 1.2MHz, allowing the use of tiny external components. The output capacitor can be as small as 0.22µF, saving space and cost versus alternative solutions. A low 95mV feedback voltage minimizes power loss in the current setting resistor for better efficiency.
The LT1937 is available in low profile SC70 and ThinSOT packages.
- Cellular Phones
- PDAs, Handheld Computers
- Digital Cameras
- MP3 Players
- GPS Receivers
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (2)
DC507A: Demo Board for the LT1937 White LED Step-Up Converter in SC70 and ThinSOT.
DC484A: Demo Board for the LT1937 White LED Step-Up Converter in SC70 and ThinSOT.
Documentation & Resources
R303 Reliability Data3/23/2018232 K
DC507A - Demo Manual9/24/2009474K
DC484A - Demo Manual9/24/2009472K
White LED Driver in Tiny SC70 Package Achieves 84% Efficiency8/1/2002 LT Journal
Tools & Simulations
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|Part Number||Material Declaration||Reliability Data||Pin/Package Drawing||CAD Symbols, Footprints & 3D Models|
|LT1937ES5#TRMPBF||Material Declaration||Reliability Data||5-Lead TSOT-23|
|LT1937ES5#TRPBF||Material Declaration||Reliability Data||5-Lead TSOT-23|
|LT1937ESC6#TRMPBF||Material Declaration||Reliability Data||6-Lead SC70|
|LT1937ESC6#TRPBF||Material Declaration||Reliability Data||6-Lead SC70|
|Wafer Fabrication Data||R303 Reliability Data|
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